rsk writes: Paul Tyma, the man behind Mailinator, has put together an excellent performance analysis comparing old-school (java.io.*) synchronous programming to Java's (java.nio.*) asynchronous programming showing a consistent 25% performance deficiency with the asynchronous code. As it turns out, old-style blocking I/O with modern threading libraries like Linux NPTL and multi-core machines gives you idle-thread and non-contending thread management for an extremely low cost; less than it takes to switch-and-restore connection state constantly with a selector approach.